Machine for producing paving aggregates



'Jhme23,1936. CELZE T L v 2,045,451

MACHINE FOR PRODUCING PAVING AGGREGATES Filed Ndv. 17', 1931 4'Sheets-Sheet 1 INVENTORS Mum? 67542: AND do 14 ATTOI'RNE Jame 23, 1936. w. c. ELZE ET AL 2,045,453

MACHINE FOR PRODUCING PAVING AGGREGATES Filed Nov. 17, 1931 4 Sheets-Sheet 2 INVENTORS, WALTER 6'. LZEAND BYL/OH/V 14 D 1/ 7r ATTORNEY June 23, 1936. w. c. ELZE ET AL 2,0

MACHINE FOR PRODUCING PAVI NG AGGREGATES Filed Nov. 17, 1931 4 Sheets-Sheet 3 INVENTORS I VALTER 62E; zsmva ATTORNEY 23, 1936. w. c. ELZE ET AL fl y MACHINE FOR PRODUCING PAVING AGGREGAT ES Filed Nov. 17', 1951 4'Sheets-Sheet 4 mvsmons MLTEA'CELzE M0 UOf/IV 1 1404 7' Patented June 23, 1936 UNITED STATES MACHINE FOR PRODUCING PAVING AGGREGATES Walter C. Elze, Forest Hills, N. Y., and John W. Davitt, Jersey City, N. J., assignors toHauck Manufacturing Company, Brooklyn, N. Y., a corporation of New York Application November 17, 1931, Serial No. 575,50!

11 Claims.

The invention relates to paving apparatus, and more especially to a machine for mixing and preparing paving materials, such as the usual aggregate consisting of an intimate mixture of a binding agent as asphalt and/or oil with sand, gravel, stone and thelike with or without the addition of lime. In accordance with the present invention this is preferably conducted upon a selfpropelled truck or like vehicle, although stationary installations may be utilized to advantage in some instances.

It has for an object the provision of a machine for the production of said aggregate which embodies means for loading a, charge of the solid materials into a mixer drum for mixing said charge and wherein it is also dried, means to introduce thereto a measured quantity. of the liquefied binder, and a storage receptacle for the mixall being mounted preferably upon a movable truck, which may be self-propelled, and carrying also burner devices and driving means for effecting the various operations involved.

A further object of the'invention involves a novel method of effecting the mixing of said materials and whereby a more thorough mix is attained.

A still further object of the invention resides in the provision of draft-inducing means in connection with the mixer drum for directing a flame therein and for disposing of products of combustion and other vapors.

Another object of the invention resides in the provision of a modified form of burner apparatus and the arrangement of the same with respect to the mixer drum.

Still another object of the invention is to afford means for conveniently shifting the said heating means for the mixer drum during the charging operation of the same.

The invention has for a still further object the provision of a novel form of discharge spout associated with the draft-inducing means and mixer drum discharge mouth or outlet.

A further object of the invention resides in the provision of measuring means for predetermining the amount of liquefied binder to be delivered to the mixer drum, and in the novel means for introducing such binder material thereto.

In carrying out the invention, the charge of material, such as sand,,gravel, crushed stone .and the like, to be mixed with a suitable binder as liquefied asphalt, oils, etc., is .arranged to be charged in the usual manner into a rotatable mixer drum and to be heated therein bya burner mdevice during the mixing operation so as to be thoroughly dried thereby. This burner device is arranged, moreover, that it may conveniently be swung aside during the charging operation so as not to interfere with the incoming charge and/or the skip or loading bucket. The construction of 5 this member, furthermore, is such that gases developing a back-pressure in the mixer drum may be vented through the burner device. 7

The charge of liquefied binder is arranged to be pumped from a storage tank on the vehicle to suitable measuring means for delivering to the mix at the discharge end of, the mixer drum a predetermined quantity of such binder material for intimate mixture therewith as the aggregate is continuously being discharged from the drum as well as with aggregate within the drum. An adequate supply of the asphalt, or the like is arranged to this end to be stored upon the vehicle in a suitable container therefor and which is also provided with heating means, provision being further made for conveniently loading the raw material into said container. 7

The charge as mixed with the asphalt andcomstituting'the completedgaggregate maybe received in a suitable chute, provisionbeing made for temporarily holding back the same as through a movable slide. closing the outlet opening. 'When said slide is withdrawn, the aggregate may be delivered directly into means for conveying it to the place of use or into a suitable storage hopper located below the mouth of thechute and which is then also'supported on the vehicle. A sufiicient quantity of the aggregate may thus be accumulated in the storage hopper from which it is eventually to be discharged for use.

In connection with the discharge of the mix into the chute, there is provided a stack or like .means for removing the products of combustion and vapors to efiect a more rapid drying action; and to induce a more positive draft through the mixer drum not only for removing these products but to assistin directing the flame jet into the interior of said drum, a jet of compressed air is arranged to be directed upwardy and substantially axially of the stack.

The nature of the invention, however, will best be understood when described in connection with the accompanying drawings, inwhich:

Fig. ,1 is a side elevation of the novel paving apparatus.

Fig.2 is a front elevation, and Fig. 3 a rear elevation thereof.

Fig. 4 is a side elevation of the pavingmachine opposite to the similar elevation shown in Fig. ,1.

Fig. .5 is a fragmentary vertical section, on an 15 enlarged scale, of the mixer drum and outlet chute therefrom, with the associated draft-inducing means, and taken on the line 55, Fig. 3.

Fig. 6 is a detail elevation of the burner utilized to direct a flame into the mixer drum.

Referring to the drawings, in designates asuitable self-propelled wheeled truck or the like having the supporting frame or chassis l 1 upon which is carried the various apparatus hereinafter described and constituting the elements of the paving machine. A rotatable mixer drum [2 is mounted upon the vehicle, being rotated in wellknown manner as from an internal combustion engine l3, which serves also to propel the vehicle. A charging platform or loading bucket 14 is arranged to be elevated also from said engine in the usual and well-known manner to supply a charge to the interior of said drum. In addition, a burner l5, preferably designed for utilizing oil, is arranged to be directed substantially axially into the mixer drum l2-and is, furthermore, pivoted at the elbow IE to swing thereabout. A handle I1 is attached to the burned end and extends backwardly toward the elbow l6 for conveniently manipulating the said burner to displace the same sufficiently to avoid an incoming charge to the mixer drum as well as the loading bucket.

In the preparation of the paving aggregate, there is designed to be mixed with the contents of the drum liquefied asphalt, oil or like binder material and usually of a bituminous nature, a supply of which is arranged to be stored in a suitable container 20 also supported by the vehicle. To introduce conveniently into the container the said binder material, there is provided on the cover 2| of said container a hoisting crane member 22, and the cover is divided so as to af ford the hinged portion 23 which may be swung back to the position indicated in dotted lines and thus afford an opening into the interior of the container.

Suitable burner apparatus 25 is located at the bottom of the container to provide the heat necessary for liquefying the asphalt or other binder material. Furthermore, a pump 26 is associated with the container, being located for example on the cover 2! thereof and operated, preferably manually, as through the crank handle 21 ro- 'tatably mounted in the superstructure of the apparatus.

This pump is designed to withdraw a charge of binder of predetermined weight from the'container 20 and deliver the same into a measuring bucket 28 from which, through the operation of the slide 29, it may be discharged into a delivery pipe 30 whose end 3! is located at the lower portion of the discharge outlet 32 of drum I2 and preferably flattened to more or less spray the binder onto the mix.

Thus, as the mix is discharged through said outlet 32, it comes in contact with the infiowing liquefied asphalt or like binder as the same flows into the lower portion of said drum. It is thereby intimately mixed therewith and eventually discharged into a chute 35 having'the opening 36 registering substantially with the outlet 32 of the drum.

Opening 36, furthermore, communicates with a stack 31, extending upwardly from the discharge end of the drum substantially to the top 'of the paving apparatus, for convenient removal of the products of combustion from the burner l5 and other vapors arising from the mixing operation. In order to enhance this flow, draftinducing means such as a jet of compressed air obtained from a compressor 38 and discharged from the nozzle 39 may be introduced into the} stack, preferably in the longitudinal axis thereof. This will serve also to afford a positive draft through the drum l2 and assist in directing the flame jet from burner I5 thereinto so that the materials being mixed therein will be uniformly heated to the desired temperature.

A slide 40 is arranged to block temporarily the passage of the mix through chute 35 and cause the same to be returned to the drum, the slide of the chute located opposite the mouth 32 of the drum to this end being inclined or curved toward said mouth. When the slide is withdrawn, the mix is permitted to discharge into a storage receptacle or hopper 4| beneath the outlet 42 of the said chute.

' It has been found that the operation of slide 49 may be greatly improved by associating therewith a scraper element 43 in the nature of a bar arranged transversely of the slide motion acrossthe chute 35 and rigidly positioned with respect to said chute. The lower edge of this bar, furthermore, is beveled or sharpened so that as the slide moves thereover it will serve to scrape therefrom any accretions of sticky mix.

In the provision of this temporarily sealed chute and the stack for the conduction of spent gases, vapors, ,etc., from the drum,it has been found that a back pressure of the gases develops within the latter which to some extent interferes with the proper action ofthe burner l5. There is a tendency not only to extinguish the burner flame but the volume of air which may be utilized in the combustion appears to be materially diminished. The sleeve or combustion chamber 45 of the burner and which is intended to be associated with the inlet of the mixer drum is to this end provided with relief or vent openings as the circumferential slots 46 at the outermost portion of the sleeve. Perforations 41 disposed circumferentially at an intermediate portion of the sleeve may serve for the induction air to assist in the combustion.

We. claim: 7

1. Paving apparatus comprising a supporting vehicle, a rotatable mixing drum and means to load the same, a burner element adapted to introduce flame into the charging mouth of said drum, a chute for receiving the discharge from said drum, means to normally close said chute to return discharged material to the drum, and draft-inducing means associated with the closedoff portion of the chute and outlet portion of the drum.

2. Paving apparatus comprising a supporting vehicle, a rotatable mixing drum and means to load the same, a burner element adapted to introduce flame into the charging mouth'of said drum, a chute for receiving the discharge from said drum, means to normally close said chute to return discharged material to the drum, and a stack associated with the closed-off portion of the chute and outlet portion of-the drum.

3. Paving apparatus comprising a' supporting vehicle, a rotatable mixing drum and means to load the same, a burner element adapted to introduce flame into the charging mouth of said drum' and having openings for venting gases from said drum, a chute for receiving the discharge from said drum, and means to normally close said chute to return discharged material to the drum. 7

4. Paving apparatus comprising a supporting veh c e, a rotatable mixing drum and means to load the same, a burner element adapted to in troduce flame into the charging mouth of said drum and having openings for venting gases from said drum, a chute for receiving the discharge from said drum, means to normally close said chute to return discharged material to the drum, and a stack associated withthe closed-01f portion of the chute and outlet portion of the drum.

5. Paving apparatus comprising a supporting vehicle, a rotatable mixing drum and means to load the same, a burner element adapted to introduce flame into the charging mouth of said drum, a chute for receiving the discharge from said drum, means to normally close said chute to return discharged material to the drum, a stack associated with the closed-off portion of the chute and outlet portion of the drum, and a nozzle mounted therein for discharging compressed air upwardly through the stack.

6. Paving apparatus comprising a supporting vehicle, a rotatable mixing drum and means to load the same, a burner element adapted to introduce flame into the charging mouth of said drum, a chute for receiving the discharge from said drum, and a slide normally closing off the chute.

7. Paving apparatus comprising a supporting vehicle, a rotatable mixing drum and means to load the same, a burner element adapted to introduce flame into the charging mouth of said drum, a chute for receiving the discharge from said drum, and a slide normally closing off the chute and inclined toward the discharge mouth of the drum.

8. In paving apparatus comprising a rotatable mixing drum: a chute for receiving the discharge from said drum, a slide normally closing off the chute, and a manually operable scraper element in fixed relation to the chute and having an edge bearing upon the slide whereby the latter may be cleared of accumulations of discharged material.

9. Paving apparatus comprising a supporting vehicle, a rotatable mixing drum provided with a charging mouth and a discharging mouth and means to load the same, a burner element adapted to introduce flame into the charging mouth of said drum, a container for liquefiable binder material, means to heat said material therein, a pump to remove a charge therefrom, measuring apparatus receiving the discharge from said pump for selecting a predetermined quantity of the liquefied binder, and means to convey the binder from said measuring apparatus to the discharging mouth of the mixer drum and to the mixed aggregate.

10. Paving apparatus comprising a supporting vehicle, a rotatable mixing drum provided with a charging mouth and a discharge mouth and means to load the same, a burner element adapted to introduce flame into the charging mouth of said drum, a container for liquefiable binder material, means to heat said material therein, a pump" to remove a charge therefrom, measuring apparatus receiving the discharge from said pump for selecting a predetermined quantity of the liquefied binder, a chute for receiving the discharge from said drum, means to close said chute to return the discharged material to the drum, a stack associated'with the closed-off portion of the chute and outlet portion of the drum, and a. pipe passing through the lower portion of the stack to convey binder from said measuring apparatus to the mouth of the mixer drum.

11. In the operation of apparatus for providing paving aggregates: the method of effecting an intimate mixture of a binder with comminuted solid material, which comprises mechanically mixing the solid material, preliminarily discharging the mixture, applying the binder thereto as the aggregate is thus discharged, and prior to final discharge of the material returning the mixed aggregate for further mechanically mix- WALTER. C. ELZE.

JOHN W. DAVITT. 

